It is recognized that there exists an increased need for protecting electrical and electronic systems present in the turret of an armored vehicle. Indeed, in these types of systems, the currents are established during microseconds while protection devices such as fuses, circuit breakers and/or electromechanical relays are only suitable for reaction times in the range of milliseconds.
Presently, a power distribution is used. Within this framework, the most enhanced systems, i.e. for example magneto-thermal switches or a combination thereof and of fuses, are slower to react since they cause a variable response of the current depending on the required reaction time.
Magneto-thermal switches have a time/overcurrent tripping curve which is an intrinsic characteristic of the component and is not programmable. One is then forced to set a maximum admissible value of the average current overtime, the system putting itself in a protection mode only if the instantaneous actual current exceeds this maximum value. As failure peaks have to be taken into account, this value should generally be quite high (for example a few tens of amperes). It ensures that one is forced to overdimension the cabling (more robust cabling, larger diameter), which entails more weight and stiffness for the latter and is therefore disadvantageous for the installation in a turret of an armored vehicle for example.
The solution for avoiding a variable current overtime is to abandon protection systems with electromechanical switches and to resort to an electronic protection without mechanical switch.
Electronic switches are known in the state of the art but the latter do not measure the current crossing them.
Document US 2013/113451 discloses a power conversion circuit comprising a voltage estimation circuit, a current estimation circuit and a pulse width modulation circuit. The voltage estimation circuit is configured for receiving an input voltage from an inductor of the power conversion circuit and for generating an estimation of an output voltage of the power conversion circuit on the basis of said voltage. The current estimation circuit is configured for receiving a current corresponding to a switch connected in series with the inductor and generating an estimation of an output current of the power conversion circuit on the basis of said current. The pulse width modulation circuit is configured for producing a pulse width modulated signal on the basis of estimation of the output voltage and of the estimation of the output current.
Document WO 2008/057386 discloses a system for remote management and monitoring of power in order to control an electrical apparatus powered by a power supply block. The system may comprise a structured circuit breaker casing for controlling and managing the power at the electrical apparatus via a centralized data bus and a centralized power bus. The circuit breaker casing may comprise at least a remotely actuated electronic circuit breaker (ECB) in the solid state which monitors and manages the power supply of the electrical apparatus and a switch connected to the ECB and capable of remotely circumventing the ECB. The system may also comprise a display and a controller which can remotely monitor and control the electrical apparatus by remotely actuating the ECB.
Document US 2006/0049694 discloses a load control system in an electrical power supply system, in which one or several load control devices are provided for controlling the power provided to the electrical equipment. An authority for managing the network remotely, such as a power company, a government body or a power transmission company, sends one or several commands to load control devices for adjusting the load on the electrical power supply system.
In one embodiment, said authority sends stopping commands. In one embodiment, the authority sends commands imposing low power mode operation to the electrical power supply device.
In one embodiment, the commands are time-limited, thus allowing the electrical power supply system to resume normal operation after a determined period of time.
In one embodiment, the commands comprise requests for having the control device report operating characteristics (for example, the yield, the operating time, etc.), back to said authority.
This application relates to the supply of alternating current through the electricity network for power applications in the residential or industrial field and uses electromechanical circuit breaker devices.
Document US 2009/0225483 discloses an electric circuit breaker device protecting an electric circuit against overload. A first remotely programmable device for triggering the circuit breaker receives an external command with a programmable current threshold, detects a current level in the electric circuit and is able to trigger an interruption in the electric circuit depending on the detected current level in relationship with a first current period associated with the programmable current threshold stored in memory. A second device for triggering the circuit breaker is laid out for triggering an interruption in the electric circuit according to a second period of current different of the first period, for example a shorter one, if a current circulating in the electric circuit exceeds a predetermined rated current during a period greater than the second period of the current. This technology, also intended for use on the electric distribution network, involves several triggering levels but reacts slowly considering the use of magneto-thermal circuit breakers.